Frames and associated cover plates for use in roads or paved surfaces



NOV. 2, 1965 s D ETAL 3,215,052

FRAMES AND AS IA COVER PLATES FOR USE IN ROADS OR PAVED FACES Filed Jan. 1962 FIG].

United States. Patent 3,215,052 FRAMES AND ASSOCIATED COVER PLATES FOR USE IN ROADS 0R PAVED SURFACES Odvar Ree Lindstad and Karl M. Kaare, both of Stange, Hamar, Norway Filed Jan. 15, 1962, Ser. No. 166,265 Claims priority, application Norway, Jan. 20, 1961,

1 Claim. (Cl. 94-34) The present invention relates to frames and associated cover plates for use on roads and other paved surfaces and which may be arranged to extend over or enclose manholes, sunken hydrants, stop cocks or valves, or electric cable and switch boxes and the like.

In road building or repairing or due to local movement of road surfacing it is frequently necessary to adjust the level of a manhole cover relative to the road surface. Previously such adjustment has required substantial work as it necessitates to dig up the frame supporting the cover to regulate the same on the top of the box to the required new level, then refixing the frame on the box top and thereafter fill in earth around the same.

An object of the present invention is to eliminate the above work and to provide a frame and cover assembly which permits that the level of the cover may be adjusted to fit possible Variations in the road surface without disturbing the frame.

A further object of the invention is to provide a simple and reliable construction comprising a minimized number of parts which may be prepared by moulding without any finish and with low material cost.

According to the invention the frame of the assembly consists of two telescopic interfittin-g cylindrical frame members, of which the upper member, supporting the cover plate, is provided on its lower end with cam means co-operating with corresponding cam means on the lower frame member supported on the top of a box or the like, so that said upper member may be vertically adjusted by rotation relatively to the lower frame member.

An embodiment of the invention is illustrated as an example, in the accompanying drawing in which:

FIGURE 1 is a sectional side view of a frame with associated cover according to the invention,

FIGURE 2 is a plan view with the left half of the cover and the upper frame part removed, and

FIGURE 3 shows on enlarged scale a detail of the frames showing a set screw for preventing movement therebetween.

As shown in the drawing the assembly consists of a lower frame member A, an upper frame member B and a cover C.

The lower frame member A comprises a ring-shaped part 1, adapted to rest on the top of a box or the like by way of an intermedaite layer of mortar or the like, and provided with an inner downwardly extending flange 2. On its upper side the part 1 has an upwardly pr-ojecting cylindrical portion 3 adapted to receive telescopically a lower cylindrical portion 4 of the upper frame member B, the upper part of which has a seat 5 for the cover plate C and a circumferential rib 6 having a greater diameter than that of the cylindrical portion 3 and an outwardly and downwardly rounded upper side as shown.

In order to obtain continuous stepless adjustment of the upper frame member B relative to the lower frame memher A the lower end of the cylindrical portion of the member B is limited by a number of cam surfaces preferably helical curves 7 evenly distributed around said end and separated by axial surfaces 8. correspondingly formed cam surfaces 7' with axial connecting surfaces 8' are arranged on a shoulder 3' at the inner circumference of the cylindrical portion 3, so that the upper frame member B rests with its cam surfaces 7 on the corresponding surfaces 7 of the lower member A. When the member B is in its lowermost position the axial surfaces 8, 8' bear against each other.

Upon clockwise rotation of the upper frame member B it screws itself upwards by co-operation between the cam surfaces 7, 7 so that the distance between the upper side of said member, and thereby of the cover plate C, and the ring-shaped part 1, resting on the box top, may be adjusted in continuous stepless fashion.

In order to retain the upper member B in an adjusted position and prevent counter clockwise revolution thereof a suitable spacer 9 is inserted between the spaced axial surfaces 8, 8' or the space between said surfaces may be filled with a suitable hardening mass, such as mortar (not shown). If desired, one or more set screws 10 may be threaded radially through the cylindrical part 4 of the upper member B and screwed against the portion 3 of the lower member A.

We claim:

As assembly for enclosing a manhole comprising a lower frame member of ring shape immovably supported in association with said manhole, said lower frame member including an upwardly directed cylindrical portion having a smooth inner surface and further including a downwardly directed cylindrical portion, an upper frame member including a downwardly directed cylindrical portion having a smooth outer surface telescopic-ally projecting within the inner surface of said cylindrical portion of the lower frame and also including a circumferential rib having a greater diameter than the latter said cylindrical portion and having an outwardly and downwardly rounded upper side and a slanted lower side, the downwardly directed cylindrical portion of the lower frame member having a smaller diameter than the downwardly directed cylindrical portion of the upper frame member, said upper frame member being freely rotatable in said lower frame member, a shoulder projecting radially inwardly on the cylindrical portion of the lower frame in contact with and supporting said upper frame member through the cylindrical portion thereof, the latter said cylindrical portion and the shoulder including respective engageable sawtooth surfaces which adjust the vertical position of the upper frame member in accordance with the angular position of the latter relative to the lower frame member, said surfaces being constituted by corresponding regularly distributed helical cam surfaces and axial surfaces connecting said'helica'l surfaces, said cam surfaces being smooth between adjacent axial surfaces .and extending over a substantial circumferential portion of the respective mating surfaces, the axial surfaces of the mating surfaces of said frame members being in abutting relation with one another in .a lowermost position of the upper frame member, said upper frame member being upward-1y adjustable in said lower frame member in continuous stepless fashion between successive axial surfaces by rotation of said upper frame member relative to the lower frame member in a direction to cause increased spacing between the axial surfaces of the upper and lower frame members, a cover having a circular outline, said upper frame member having an upper end seat in the inner surface thereof, said cover resting on said seat in said upper frame member and being raised and lowered together therewith, and a spacer resting on a helical surface of the lower member and wedged between corresponding axial surfaces of the upper and lower frame members to hold the upper frame member in an adjusted vertical position.

References Cited by the Examiner UNITED STATES PATENTS 638,692 12/99 Barnwell 94-34 689,224 12/01 Pillsbury 94-34 Tyler 94-34 Calhoun 94-34 Lincoln 94-34 Gschwind 9434 CHARLES 'E. OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, Examiner. 

